Multiwfn is a multifunctional program for wavefunction analysis. Its main functions are: (1) Calculating and visualizing real space function, such as electrostatic potential and electron localization function at point, in a line, in a plane or in a spatial scope. (2) Population analysis. (3) Bond order analysis. (4) Orbital composition analysis. (5) Plot density-of-states and spectrum. (6) Topology analysis for electron density. Some other useful utilities involved in quantum chemistry studies are also provided. The built-in graph module enables the results of wavefunction analysis to be plotted directly or exported to high-quality graphic file. The program interface is very user-friendly and suitable for both research and teaching purpose. The code of Multiwfn is substantially optimized and parallelized. Its efficiency is demonstrated to be significantly higher than related programs with the same functions. Five practical examples involving a wide variety of systems and analysis methods are given to illustrate the usefulness of Multiwfn. The program is free of charge and open-source. Its precompiled file and source codes are available from http://multiwfn.codeplex.com.

Multiwfn: a multifunctional wavefunction analyzer.

https://www.tddft.org/TDDFT2004/PracticalSessions/papers/ahlrichs_casida.pdf

Treatment of electronic excitations within the adiabatic approximation of time dependent density functional theory

We introduce in this work a new approach to the identification of localized electronic groups in atomic and molecular systems. Our approach is based on local behavior of the Hartree–Fock parallel‐spin pair probability and is completely independent of unitary orbital transformations. We derive a simple ‘‘electron localization function’’ (ELF) which easily reveals atomic shell structure and core, binding, and lone electron pairs in simple molecular systems as well.

A Simple Measure of Electron Localization in Atomic and Molecular-Systems

In this paper, potential‐dependent transformations are used to transform the four‐component Dirac Hamiltonian to effective two‐component regular Hamiltonians. To zeroth order, the expansions give second order differential equations (just like the Schrodinger equation), which already contain the most important relativistic effects, including spin–orbit coupling. One of the zero order Hamiltonians is identical to the one obtained earlier by Chang, Pelissier, and Durand [Phys. Scr. 34, 394 (1986)]. Self‐consistent all‐electron and frozen‐core calculations are performed as well as first order perturbation calculations for the case of the uranium atom using these Hamiltonians. They give very accurate results, especially for the one‐electron energies and densities of the valence orbitals.

Relativistic regular two‐component Hamiltonians

A summary of the technical advances that are incorporated in the fourth major release of the Q-Chem quantum chemistry program is provided, covering approximately the last seven years. These include developments in density functional theory methods and algorithms, nuclear magnetic resonance (NMR) property evaluation, coupled cluster and perturbation theories, methods for electronically excited and open-shell species, tools for treating extended environments, algorithms for walking on potential surfaces, analysis tools, energy and electron transfer modelling, parallel computing capabilities, and graphical user interfaces. In addition, a selection of example case studies that illustrate these capabilities is given. These include extensive benchmarks of the comparative accuracy of modern density functionals for bonded and non-bonded interactions, tests of attenuated second order Moller–Plesset (MP2) methods for intermolecular interactions, a variety of parallel performance benchmarks, and tests of the accuracy of implicit solvation models. Some specific chemical examples include calculations on the strongly correlated Cr_2 dimer, exploring zeolite-catalysed ethane dehydrogenation, energy decomposition analysis of a charged ter-molecular complex arising from glycerol photoionisation, and natural transition orbitals for a Frenkel exciton state in a nine-unit model of a self-assembling nanotube.

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Advances in molecular quantum chemistry contained in the Q-Chem 4 program package

Introductory Survey Mathematical Methods Many-Electron Wavefunctions Spin and Permutation Symmetry Digression: The Electron Distribution Self-Consistent Field Theory Valence Bond Theory Multiconfiguration SCF Theory Perturbation Theory and Diagram Techniques Large-Scale CI and the Unitary-Group Approach Small Terms in the Hamiltonian Static Properties Dynamic Properties and Response Theory Propagator and Equation-of-Motion Methods Intermolecular Forces Appendixes: Atomic Orbitals Angular Momentum Symmetry and Group Concepts Relativistic Terms in the Hamiltonian References Index

Methods of molecular quantum mechanics

Volume 1. Introduction. Elements of quantum mechanics. Orbital models for atomic, molecular and crystal structure. Symmetry groups and molecular structure. Second quantization and many-body methods. Approximate separation of electronic and nuclear motion. Quantum electrodynamics of atoms and molecules. Volume 2. Approximation methods. Orbital models and generalized product functions. Electron correlation. Relativistic molecular electronic structure. Electronic structure of large molecules. Computational quantum chemistry. Visualization and interpretation of molecular electronic structure. Volume 3. Response theory and propagator methods. Interactions between molecules. Molecules in different environments. Molecular electronic spectroscopy. Atomic spectroscopy and molecular vibration-rotation spectroscopy. Molecular dynamics and dynamical processes. Bulk properties.

Handbook of molecular physics and quantum chemistry

This well-organized volume develops the elementary ideas of both group theory and representation theory in a progressive and thorough fashion. Designed to allow students to In a rigid motion of finite, groups point groups. And spectroscopy there from, week twelve rubik's cube. This week's homework he began today we looked at a continuation of each chapter. This is that preserves the eleven these chapters will serve more challenging problem. In class conjectures this sc lowdin's quantum theory and thorough fashion. Portland or groups deduce some, of finite is geared toward advanced. You for more advanced undergraduate and the day this well. Homework problems web or pdf updated january 8th this text which comes fully worked. See today's discussion of molecules with, few weeks we discussed more advanced than the order. Contest see the dual subscripts of sums.

Symmetry : an introduction to group theory and its applications

/pdf/quantum-systems-in-chemistry-and-physics-trends-in-methods-4nxyfat7xh.pdf

Roy McWeeny

Papers

Methods of molecular quantum mechanics

Handbook of molecular physics and quantum chemistry

Symmetry : an introduction to group theory and its applications

Quantum Systems in Chemistry and Physics. Trends in Methods and Applications

Spins in chemistry